ceph/src/boost/libs/spirit/include/boost/spirit/home/support/has_semantic_action.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Hartmut Kaiser
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 ==============================================================================*/
   7 #if !defined(BOOST_SPIRIT_HAS_SEMANTIC_ACTION_SEP_20_2009_0626PM)
   8 #define BOOST_SPIRIT_HAS_SEMANTIC_ACTION_SEP_20_2009_0626PM
   9
  10 #if defined(_MSC_VER)
  11 #pragma once
  12 #endif
  13
  14 #include <boost/mpl/bool.hpp>
  15 #include <boost/mpl/or.hpp>
  16 #include <boost/mpl/not.hpp>
  17 #include <boost/mpl/find_if.hpp>
  18 #include <boost/type_traits/is_same.hpp>
  19
  20 namespace boost { namespace spirit { namespace traits
  21 {
  22     // finding out, whether a component contains a semantic action
  23     template <typename T, typename Enable = void>
  24     struct has_semantic_action
  25       : mpl::false_ {};
  26
  27     template <typename Subject>
  28     struct unary_has_semantic_action
  29       : has_semantic_action<Subject> {};
  30
  31     template <typename Left, typename Right>
  32     struct binary_has_semantic_action
  33       : mpl::or_<has_semantic_action<Left>, has_semantic_action<Right> > {};
  34
  35     template <typename Elements>
  36     struct nary_has_semantic_action
  37       : mpl::not_<
  38             is_same<
  39                 typename mpl::find_if<
  40                     Elements, has_semantic_action<mpl::_>
  41                 >::type
  42               , typename mpl::end<Elements>::type
  43             >
  44         > {};
  45 }}}
  46
  47 #endif